2-Layer RO4350B LoPro PCB 4mil Rogers Substrate Immersion Gold Blue Solder Mask

2-Layer RO4350B LoPro PCB 4mil Rogers Substrate Immersion Gold Blue Solder Mask

1. Product Overview

This is a 2-layer high-frequency rigid PCB built on Rogers RO4350B LoPro hydrocarbon-ceramic laminate with a 4mil (0.102mm) dielectric core and immersion gold surface finish. It is engineered for ultra-low insertion loss, stable dielectric performance, excellent thermal reliability, and compatibility with standard PCB fabrication processes. Unlike conventional high-frequency materials, it combines low conductor loss from reverse-treated foil, tight impedance control, and cost-effective manufacturability, making it ideal for RF antennas, power amplifiers, satellite LNBs, high-speed backplanes, and RFID systems.

2. PCB Construction Details

This section summarizes the mechanical, electrical, and surface finishing parameters that define board robustness and assembly compatibility.

3. PCB Stackup

This table defines the layer structure and thicknesses for impedance and high-frequency performance modeling.

4. PCB Layout Statistics

This section summarizes routing complexity, pad count, and interconnection structure for assembly and reliability analysis.

5. Core Technical Advantages & Differentiation

5.1 Low Conductor Loss & Signal Integrity

RO4350B LoPro uses Rogers’proprietary reverse-treated foil technology, which significantly reduces surface roughness and conductor loss compared with standard ED foil. This lowers insertion loss and improves signal integrity, especially above 10 GHz. The design supports frequencies beyond 40 GHz while maintaining stable impedance and low phase distortion.

5.2 Stable Dielectric Properties

• At 10 GHz / 23°C:
• Dielectric constant (Dk): 3.48±0.05
• Dissipation factor (Df): 0.0037

These values remain consistent across wide frequency and temperature ranges, supporting broadband designs and high-volume manufacturing repeatability.

5.3 Excellent Thermal Reliability

• Tg > 280°C (TMA)
• Decomposition temperature Td > 390°C
• Thermal conductivity: 0.69 W/m·K
• CTE X:10, Y:12, Z:32 ppm/°C (−55 to 288°C)

Matched CTE with copper minimizes thermal stress and ensures reliable plated through-holes (PTHs) under thermal cycling.

5.4 Process & Cost Efficiency

• Fabrication compatible with standard FR-4 processes
• No special via etching (e.g., sodium etch) required
• Lead-free reflow compatible
• UL 94 V-0 flammability
• CAF resistance for high-voltage / high-humidity environments

5.5 Mechanical & Assembly Stability

• Ultra-thin 0.2 mm overall board for compact modules
• Blue solder mask (top) for optical recognition
• Immersion gold for flat, solderable, corrosion-resistant pads
• 100% electrical test to eliminate opens, shorts, and impedance anomalies

6. Typical Applications

• Cellular base station antennas and power amplifiers
• Satellite LNBs and RF front-ends
• High-speed digital backplanes, servers, routers
• RFID tags and wireless identification systems
• Test instruments and wideband RF modules

Part 2–CCL (Copper Clad Laminate) Technical Knowledge

This section provides detailed, datasheet-level CCL education for Rogers RO4350B LoPro, separated from PCB description to avoid repetition. It includes full parameter tables, material science, and application logic.

1. What is RO4350B LoPro CCL?

Rogers 4350B LoPro is a glass-reinforced hydrocarbon-ceramic high-frequency laminate from Rogers Corporation. It usesreverse-treated low-profile copper foilbonded to RO4350B dielectric resin to reduce conductor loss while preserving the base material’s electrical and thermal stability. It bridges the performance gap between standard RO4350B and premium PTFE materials but with FR-4 compatible processing and lower total cost.

2. Full Datasheet Parameter Table (RO4350B LoPro CCL)

3. Key CCL Performance Mechanisms

3.1 Low-Loss Design Principle

• Low Dk / Low Df: Reduces signal delay and attenuation.
• Low-profile foil: Reduces skin-effect loss at high frequencies.
• Ceramic-filled hydrocarbon: Balances electrical performance and processability.

3.2 Thermal Stability

High Tg and low Z-axis CTE prevent via cracking and delamination during reflow and thermal cycling. Thermal conductivity efficiently dissipates heat in high-power RF circuits.

3.3 Manufacturing Compatibility

• Drillable with standard bits
• Standard desmear vs. PTFE’s special etching
• Stable lamination windows
• Good for mass production

3.4 Reliability Features

• Low moisture absorption preserves Dk/Df in humid environments
• CAF resistance prevents conductive filament growth
• V-0 flame rating for safety-critical use cases

4. Why RO4350B LoPro CCL Stands Out

• Lower insertion loss than standard RO4350B
• Lower PIM for base station antennas
• Better impedance control for microwave designs
• Cost lower than PTFE materials
• Process compatible with FR-4 lines
• Stable across frequency/temp for broadband products

5. CCL Selection Guidance for High-Frequency PCBs

• Dk stability > narrow tolerance for impedance control
• Df as low as possible > minimize loss
• CTE matching > prevent thermal fatigue
• Trenchability & drillability > lower cost
• Thermal performance > for high power
• Moisture/CAF/flammability > for harsh environments

Conclusion

The RO4350B LoPro Immersion Gold PCB delivers verified low-loss, high-stability performance for demanding RF and high-speed systems. Its combination of Rogers’advanced CCL technology, precision fabrication, and IPC-Class-2 quality makes it a reliable, cost-effective solution for volume production in 5G, satellite, and high-speed digital infrastructure.